Module org.apache.lucene.misc

Package org.apache.lucene.misc.store

Class DirectIODirectory.DirectIOIndexInput

java.lang.Object

org.apache.lucene.store.DataInput

org.apache.lucene.store.IndexInput

org.apache.lucene.misc.store.DirectIODirectory.DirectIOIndexInput

All Implemented Interfaces:

Closeable, AutoCloseable, Cloneable

Enclosing class:

DirectIODirectory

private static final class DirectIODirectory.DirectIOIndexInput
extends IndexInput

Field Summary

Fields

Modifier and Type	Field	Description
private final int	blockSize
private final ByteBuffer	buffer
private final FileChannel	channel
private long	filePos
private boolean	isClone
private boolean	isOpen

Constructor Summary

Constructors

Modifier	Constructor	Description
	DirectIOIndexInput(Path path, int blockSize, int bufferSize)	Creates a new instance of DirectIOIndexInput for reading index input with direct IO bypassing OS buffer
private	DirectIOIndexInput(DirectIODirectory.DirectIOIndexInput other)

Method Summary

Modifier and Type	Method	Description
DirectIODirectory.DirectIOIndexInput	clone()	Returns a clone of this stream.
void	close()	Closes the stream to further operations.
long	getFilePointer()	Returns the current position in this file, where the next read will occur.
long	length()	The number of bytes in the file.
byte	readByte()	Reads and returns a single byte.
void	readBytes(byte[] dst, int offset, int len)	Reads a specified number of bytes into an array at the specified offset.
private void	refill(int bytesToRead)
void	seek(long pos)	Sets current position in this file, where the next read will occur.
IndexInput	slice(String sliceDescription, long offset, long length)	Creates a slice of this index input, with the given description, offset, and length.

Methods inherited from class org.apache.lucene.store.IndexInput

getFullSliceDescription, randomAccessSlice, skipBytes, toString

Methods inherited from class org.apache.lucene.store.DataInput

readBytes, readFloats, readGroupVInt, readGroupVInts, readInt, readInts, readLong, readLongs, readMapOfStrings, readSetOfStrings, readShort, readString, readVInt, readVLong, readZInt, readZLong

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

buffer

private final ByteBuffer buffer

channel

private final FileChannel channel

blockSize

private final int blockSize

isOpen

private boolean isOpen

isClone

private boolean isClone

filePos

private long filePos

Constructor Details

DirectIOIndexInput

public DirectIOIndexInput(Path path,
 int blockSize,
 int bufferSize)
                   throws IOException

Creates a new instance of DirectIOIndexInput for reading index input with direct IO bypassing OS buffer

Throws:

UnsupportedOperationException - if the JDK does not support Direct I/O

IOException - if the operating system or filesystem does not support support Direct I/O or a sufficient equivalent.

DirectIOIndexInput

private DirectIOIndexInput(DirectIODirectory.DirectIOIndexInput other)
                    throws IOException

Throws:

IOException

Method Details

close

public void close()
           throws IOException

Description copied from class: IndexInput

Closes the stream to further operations.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Specified by:

close in class IndexInput

Throws:

IOException

getFilePointer

public long getFilePointer()

Description copied from class: IndexInput

Returns the current position in this file, where the next read will occur.

Specified by:

getFilePointer in class IndexInput

See Also:

• IndexInput.seek(long)

seek

public void seek(long pos)
          throws IOException

Description copied from class: IndexInput

Sets current position in this file, where the next read will occur. If this is beyond the end of the file then this will throw EOFException and then the stream is in an undetermined state.

Specified by:

seek in class IndexInput

Throws:

IOException

See Also:

• IndexInput.getFilePointer()

length

public long length()

Description copied from class: IndexInput

The number of bytes in the file.

Specified by:

length in class IndexInput

readByte

public byte readByte()
              throws IOException

Description copied from class: DataInput

Reads and returns a single byte.

Specified by:

readByte in class DataInput

Throws:

IOException

See Also:

• DataOutput.writeByte(byte)

refill

private void refill(int bytesToRead)
             throws IOException

Throws:

IOException

readBytes

public void readBytes(byte[] dst,
 int offset,
 int len)
               throws IOException

Description copied from class: DataInput

Reads a specified number of bytes into an array at the specified offset.

Specified by:

readBytes in class DataInput

Parameters:

dst - the array to read bytes into

offset - the offset in the array to start storing bytes

len - the number of bytes to read

Throws:

IOException

See Also:

• DataOutput.writeBytes(byte[],int)

clone

public DirectIODirectory.DirectIOIndexInput clone()

Description copied from class: IndexInput

Returns a clone of this stream.

Clones of a stream access the same data, and are positioned at the same point as the stream they were cloned from.

Expert: Subclasses must ensure that clones may be positioned at different points in the input from each other and from the stream they were cloned from.

Warning: Lucene never closes cloned IndexInputs, it will only call IndexInput.close() on the original object.

If you access the cloned IndexInput after closing the original object, any readXXX methods will throw AlreadyClosedException.

This method is NOT thread safe, so if the current IndexInput is being used by one thread while clone is called by another, disaster could strike.

Overrides:

clone in class IndexInput

slice

public IndexInput slice(String sliceDescription,
 long offset,
 long length)

Description copied from class: IndexInput

Creates a slice of this index input, with the given description, offset, and length. The slice is sought to the beginning.

Specified by:

slice in class IndexInput